(508338) 2015 SO20
| Discovery[1][2][3] | |
|---|---|
| Discovered by | M. E. Schwamb |
| Discovery site | La Silla Obs. |
| Discovery date | 8 October 2010 |
| Designations | |
| 2010 TF182 | |
| TNO[1] · E-SDO[4] distant[2] · detached extreme | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 2 | |
| Observation arc | 6.96 yr (2,543 days) |
| Aphelion | 290.09 AU |
| Perihelion | 33.164 AU |
| 161.63 AU | |
| Eccentricity | 0.7948 |
| 2054.81 yr (750,519 d) | |
| 0.0032° | |
| 0° 0m 1.8s / day | |
| Inclination | 23.451° |
| 33.619° | |
| 354.80° | |
| Physical characteristics | |
| Dimensions | 221 km (calculated)[5] 222 km (calculated)[4] |
| 0.08 (assumed)[5] 0.09 (assumed)[4] | |
| Prominent water (H 2O/"bowl" type)[6]: 6 | |
| 6.5[1] · 6.7[5] | |
(508338) 2015 SO20 is an extreme trans-Neptunian object and extended scattered disc object from the outermost region of the Solar System, approximately 220 kilometers (140 miles) in diameter.
Description
[edit]2015 SO20 was first observed as 2010 TF182 on 8 October 2010, by American astronomer Megan Schwamb at ESO's La Silla Observatory in northern Chile.[2] It has also been observed as 2015 SO20 during the Calar Alto TNO Survey (Z79) at the Calar Alto Observatory, Spain, on 20 September 2015.[3]
It orbits the Sun at a distance of 33.2–290.1 AU once every 2054 years and 9 months (semi-major axis of 161 AU). Its orbit has an eccentricity of 0.79 and an inclination of 23° with respect to the ecliptic.[1]
Extended scattered disc
[edit]It is one of a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more.[7] Such objects can not reach such orbits without some perturbing object, which leads to the speculation of Planet Nine.
Physical characteristics
[edit]Based on an absolute magnitude of 6.5 and an assumed albedo of 0.09, Johnston's Archive calculated a mean-diameter of 222 kilometers.[4] Michael Brown estimates an albedo of 0.08 with a diameter of 221 kilometers using an absolute magnitude of 6.7.[5]
See also
[edit]References
[edit]- ^ a b c d e "JPL Small-Body Database Browser: 508338 (2015 SO20)" (2017-09-24 last obs.). Jet Propulsion Laboratory. Retrieved 14 October 2017.
- ^ a b c "(508338) 2015 SO20". Minor Planet Center. Retrieved 14 October 2017.
- ^ a b "List Of Centaurs and Scattered-Disk Objects". Minor Planet Center. Retrieved 14 October 2017.
- ^ a b c d "List of known Trans-Neptunian Objects". Johnston's Archive. Retrieved 14 October 2017.
- ^ a b c d Michael E. Brown. "How many dwarf planets are there in the outer solar system?". California Institute of Technology. Retrieved 9 December 2017.
- ^ Pinilla-Alonso, Noemí; Brunetto, Rosario; De Prá, Mário N.; Holler, Bryan J.; Hénault, Elsa; Feliciano, Ana Carolina de Souza; et al. (December 2024). "A JWST/DiSCo-TNOs portrait of the primordial Solar System through its trans-Neptunian objects" (PDF). Nature Astronomy. 9 (2): 230–244. Bibcode:2025NatAs...9..230P. doi:10.1038/s41550-024-02433-2. S2CID 274932942.
- ^ minorplanetcenter.net: q>30, a>150
External links
[edit]- List Of Centaurs and Scattered-Disk Objects, Minor Planet Center
- List of known Trans-Neptunian Objects, Johnston's Archive
- Discovery Circumstances: Numbered Minor Planets (505001)-(510000) – Minor Planet Center
- (508338) 2015 SO20 at AstDyS-2, Asteroids—Dynamic Site
- (508338) 2015 SO20 at the JPL Small-Body Database
